<template>
  <div class="article-list">
    <van-pull-refresh
      v-model="isRefreshLoading"
      :success-text="refreshSuccessText"
      :success-duration="1500"
      @refresh="onRefresh"
    >
      <van-list
        v-model="loading"
        :finished="finished"
        finished-text="没有更多了"
        @load="onLoad"
      >
        <article-item
          v-for="(article, item) in articles"
          :key="item"
          :article="article"
        />
        <!-- <van-cell
          v-for="(article, index) in articles"
          :key="index"
          :title="article.title"
        /> -->
      </van-list>
    </van-pull-refresh>
  </div>
</template>

<script>
import { getArticles } from "@/api/article";
import ArticleItem from "@/components/article-item";
export default {
  name: "ArticleList",
  components: {
    ArticleItem,
  },
  props: {
    channel: {
      type: Object,
      required: true,
    },
  },
  data() {
    return {
      articles: [], //数据列表
      loading: false,
      finished: false,
      timestamp: null, //获取下一页数据的时间戳
      isRefreshLoading: false,
      refreshSuccessText: "",
    };
  },
  computed: {},
  watch: {},
  created() {},
  mounted() {},
  methods: {
    async onLoad() {
      // 1.请求获取数据
      const { data } = await getArticles({
        channel_id: this.channel.id,
        timestamp: this.timestamp || Date.now(),
        with_top: 1,
      });

      //数据放到list数组中
      const { results } = data.data;
      this.articles.push(...results);

      //设置本次加载状态结束
      this.loading = false;

      //数据全部加载完成
      if (results.length) {
        this.timestamp = data.data.pre_timestamp;
      } else {
        this.finished = true;
      }
    },

    async onRefresh() {
      // 下拉刷新，组件自己就会展示 loading 状态
      // 1. 请求获取数据
      const { data } = await getArticles({
        channel_id: this.channel.id, // 频道 ID
        timestamp: Date.now(), // 为了大家方便学习，只要你传递不同的时间戳就一定给你返回不一样的数据，而且数据不为空
        with_top: 1,
      });

      // 2. 把数据放到数据列表中（往顶部追加）
      const { results } = data.data;
      this.articles.unshift(...results);

      // 3. 关闭刷新的状态 loading
      this.isRefreshLoading = false;

      this.refreshSuccessText = `更新了${results.length}条数据`;
    },
  },
};
</script>

<style scoped lang="less">
.article-list {
  position: fixed;
  left: 0;
  right: 0;
  top: 90px;
  bottom: 50px;
  overflow-y: auto;
}
</style>